JP6035231B2 - Display control apparatus and electronic device - Google Patents

Description

  The present invention relates to a display control device and an electronic apparatus including the display control device, and more particularly to a technique for displaying an image indicating a power mode.

  2. Description of the Related Art Conventionally, electronic devices having a plurality of control units such as a panel control unit that controls display of an image on a display unit such as a liquid crystal display (LCD) and a system control unit that performs overall control of the entire electronic device have been provided. Are known. In such an electronic device, the power mode is switched between a normal mode in which all the control units are in a power supply state and a sleep mode in which some control units that are considered unnecessary are in a non-power supply state. It is known to suppress excessive power consumption.

  For example, Patent Document 1 below describes an image forming apparatus configured by a combination of a plurality of units (control units). The image forming apparatus includes, as units, a main system that controls the entire apparatus, an operation unit control system that controls display on the LCD, and a plotter unit that realizes a print function. In addition, the image forming apparatus supplies power only to the normal operation mode (normal mode) for supplying power to all units, the main system and the operation unit control system, and stops the supply of power to other units. The start mode (power mode) is switched between the modes (sleep mode).

  The image forming apparatus starts up in a normal operation mode at the beginning of powering on the apparatus. The main system and the operation unit control system each start a predetermined initial operation when power is supplied. After the initial operation is completed, the operation unit control system enters a standby state waiting for communication start from the main system. On the other hand, the main system establishes communication with the operation unit control system after completion of the initial operation. Thereafter, the main system appropriately controls the operation unit control system by transmitting setting information and operation commands to the operation unit control system.

  The image forming apparatus shifts the activation mode from the normal operation mode to the energy saving mode when a predetermined condition such as no operation input for a certain period of time is satisfied when the activation mode is the normal operation mode. At the beginning of the transition, the main system transmits device information indicating the number of sheets of paper accommodated in the device and the connection status of peripheral devices to the operation unit control system. On the other hand, the operation unit control system stores the received device information in the RAM, and then transmits a transition approval notification to the main system. When the main system receives the notification of transition approval, the main system cuts off the power supply to units other than the main system and the operation unit control system, and further cuts off the power supply to the LCD.

  In addition, when the activation mode is the energy saving mode, the image forming apparatus changes the activation mode from the energy saving mode to the normal mode when a predetermined return condition such as a soft switch is pressed or data is received from another apparatus is satisfied. Return to operation mode. When returning to the normal operation mode by pressing the soft switch, the main system outputs a signal indicating that it is necessary to display information on the LCD to the operation unit control system. On the other hand, when returning to the normal operation mode by receiving data from another device, the main system outputs a signal indicating that display of information on the LCD is unnecessary to the operation unit control system.

  In response to this, when a signal indicating that the display of information on the LCD is necessary when the operation unit control system returns from the energy saving mode to the normal operation mode, the operation unit control system stores the device stored in the RAM. After displaying information based on the information on the LCD, it waits for communication with the main system. On the other hand, when a signal indicating that display of information on the LCD is unnecessary is input, communication with the main system is waited without displaying information on the LCD.

JP 2008-229990 A

  However, in the technique described in Patent Document 1, the main control unit (main system) and the panel control unit (operation unit control system) are set in a power supply state in the sleep mode (energy saving mode). That is, in the technique described in Patent Document 1, there is a possibility that power is consumed in the main control unit and the panel control unit in the sleep mode, and there is room for improvement in suppressing power consumption in the sleep mode.

  In the technique described in Patent Document 1, the LCD is in a non-powered state in the sleep mode. For this reason, the user hides the LCD because the power mode is the sleep mode, or because the electronic device is not turned on. It was not possible to determine whether it was.

  In the technique described in Patent Document 1, when the soft switch is pressed to return from the sleep mode to the normal mode (normal operation mode), the operation control system performs the main control while the initial operation of the main system is incomplete. Information based on device information is displayed on the LCD regardless of control by the system. For this reason, after the user presses the soft switch, the user notices that the information based on the device information is displayed on the LCD, and the return to the normal mode is completed even though the initial operation of the main system is incomplete. There was a risk of misunderstanding. In this case, although the user starts a desired operation on the apparatus, the initial operation of the main system is incomplete, so that the operation is not effective, and there is a possibility that the user may feel annoyed.

  The present invention has been made to solve the above-described problem, and can provide a display control device capable of suppressing power consumption in the sleep mode and allowing the user to accurately grasp the current power mode. An object is to provide an electronic apparatus including the display control device.

A display control device according to the present invention controls a display device including a display unit that displays an image, an image storage unit that stores an image, a panel control unit that controls the display device, and the panel control unit. A main control unit, a normal mode in which the display device, the panel control unit, and the main control unit are in a power supply state; a power supply state in the display device; and a non-power supply in the panel control unit and the main control unit An energy-saving control unit that switches a power mode between the sleep mode and the main control unit, when the energy-saving control unit switches the power mode to the sleep mode, the power mode is Sleep display image indicating sleep mode and display during return indicating that the power mode is returning from the sleep mode to the normal mode After transmitting the image to the panel controller, becomes unpowered state, the panel control unit, the transmission has been the sleep display image and the return in the displayed image, the image stored in the image storage unit as the target of an image to be displayed on the display unit of, after a first signal indicating said sleep display image was output to the display device, Ri Do the unpowered state, said display device, the sleep display When the image, the display image during return, and the first signal are input, the input sleep display image and the display display during return are stored in the image storage unit, and the input first The sleep display image indicated by the signal is read from the image storage unit, and the sleep display image is displayed on the display unit .

  According to this configuration, when the power mode is switched to the sleep mode by the energy saving control unit, the main control unit and the panel control unit are in a non-powered state. For this reason, when the power mode is the sleep mode, the main control unit and the panel control unit are consumed when the power mode is the sleep mode, as compared with the configuration in which the main control unit and the panel control unit are in the power supply state. Power consumption can be suppressed.

  Further, according to the configuration of the display control device, when the power mode is switched to the sleep mode, the sleep display image and the returning display image transmitted by the main control unit are stored in the image storage unit, and the sleep display is displayed on the display unit. An image is displayed. Even when the power mode is the sleep mode, the display device is in a power supply state.

  For this reason, the display device can continue to display the sleep display image on the display unit while the power mode is the sleep mode. As a result, the user can accurately grasp that the current power mode is the sleep mode by viewing the sleep display image while the power mode is the sleep mode.

  Further, it is assumed that the power mode is switched from the sleep mode to the normal mode, and the main control unit and the panel control unit are in a power supply state. And, for example, when the predetermined initialization process that is initially performed when the main control unit is in the power supply state has not been completed, the predetermined initialization process that is initially performed when the panel control unit is in the power supply state is completed. . In this case, since the display device is in the power supply state while the power mode is the sleep mode, it is possible to maintain the state where the display image during restoration is stored in the image storage unit. As a result, the panel control unit can control the display device without the control by the main control unit after the initialization process is completed, and can display the display image during return stored in the image storage unit on the display unit. it can. As a result, by visually recognizing the display image during return, the user has not finished the predetermined initialization process that is initially performed when the main control unit enters the power supply state, and the power mode is returning from the sleep mode to the normal mode. It is possible to grasp exactly what is happening.

Further, the panel control unit is a target to be displayed on the display unit among the images stored in the image storage unit when the energy saving control unit switches the power mode from the sleep mode to the normal mode. As the image, a second signal indicating the display image during return is output to the display device. When the second signal is input, the display device indicates the input second signal. It is preferable that the display image during return is read from the image storage unit and the display image during return is displayed on the display unit .

  According to this configuration, when the power mode is switched from the sleep mode to the normal mode, the panel control unit even when the predetermined initialization process performed at the beginning when the main control unit is in the power supply state has not been completed. Thus, the returning display image stored in the image storage unit is displayed on the display unit. For this reason, the user does not finish the predetermined initialization process that is initially performed when the main control unit enters the power supply state by visually recognizing the display image during return, and the power mode is returning from the sleep mode to the normal mode. It is possible to grasp exactly what is happening.

  The display device receives a reset signal indicating a high level or a low level. When the input reset signal indicates a high level, the display unit displays an image while the input reset signal is displayed. When the signal indicates a low level, an image is not displayed on the display unit, and the panel control unit outputs the reset signal indicating a low level when the power supply is in a non-powered state, and the display control device It is preferable to further include a signal switching unit that switches the reset signal output from the control unit to the reset signal indicating a high level and outputs the signal to the display device.

  According to this configuration, when the power mode is switched to the sleep mode, the signal switching unit outputs a high-level reset signal to the display device even when the panel control unit is in a non-powered state. . For this reason, the display device can continue displaying the sleep display image without hiding the sleep display image displayed when the power mode is switched to the sleep mode while the power mode is the sleep mode. .

  An electronic apparatus according to the present invention is an electronic apparatus including the display control device, and includes an input operation unit that allows a user to input an operation instruction to the electronic apparatus.

  According to this configuration, in the electronic device, power consumption in the sleep mode can be suppressed, and the current power mode can be accurately grasped by the user.

  According to the present invention, it is possible to provide a display control device capable of suppressing power consumption during the sleep mode and allowing the user to accurately grasp the current power mode, and an electronic apparatus including the display control device. can do.

1 is a block diagram showing an electrical configuration of a copying machine according to an embodiment of an electronic apparatus of the present invention. It is a block diagram which shows the electric constitution of the display control apparatus which concerns on one Embodiment of the display control apparatus of this invention. It is a sequence diagram which shows an example of operation | movement of the display control apparatus at the time of power activation. It is a sequence diagram which shows an example of operation | movement of a display control apparatus when a power mode is switched from normal mode to sleep mode. It is a sequence diagram which shows an example of operation | movement of a display control apparatus when a power mode is switched from sleep mode to normal mode.

  Hereinafter, an embodiment of an electronic apparatus according to the invention will be described with reference to the drawings. In this embodiment, a copying machine is described as an example of an electronic device. However, the electronic device is not limited to this. For example, the electronic device may be an image processing device such as a printer, a facsimile device, or a scanner, or these image processing devices. A multifunction device, a game machine, a mobile phone, and a car navigation device having the functions of the device may be used.

  FIG. 1 is a block diagram showing an electrical configuration of a copying machine 1 according to an embodiment of an electronic apparatus of the present invention. As shown in FIG. 1, the copier 1 includes an input operation unit 80, a main control unit 20, a panel control unit 30, an LCD module 40 (display device), an image formation control unit 50, and a power supply unit 90. The energy saving control unit 10 is provided.

  The input operation unit 80 includes various keys for allowing the user to input operation instructions for the copying machine 1. For example, the input operation unit 80 includes various keys such as a numeric keypad for inputting numerical values and symbols, a mode switching key for inputting an instruction to switch a power mode, which will be described later, and a start key for inputting a print execution instruction. Contains the key. The input operation unit 80 outputs a signal indicating an operation instruction associated with the pressed key to the energy saving control unit 10 and the main control unit 20.

  The main control unit 20 includes a CPU (Central Processing Unit) (not shown), a nonvolatile memory (not shown) such as an EEPROM in which a control program executed by the CPU is stored, and a memory for temporarily storing data. A peripheral circuit such as a communication interface circuit for performing communication between the illustrated RAM (Random Access Memory) and the panel control unit 30 and the image formation control unit 50 is provided.

  The main control unit 20 communicates with the panel control unit 30 and the image formation control unit 50 by the CPU executing a control program stored in the nonvolatile memory, and the panel control unit 30 and the image formation control unit. Control 50. The nonvolatile memory included in the main control unit 20 includes initial conditions for the image forming operation such as the total number of sheets on which an image forming operation described below has been performed, initial density values when an image is formed on the sheet, and the like. Various data used for control of the panel control unit 30 and the image formation control unit 50 such as image data indicating an image to be displayed on the LCD 41 are stored. Details of the main control unit 20 will be described later.

  The panel control unit 30 includes a CPU (not shown), a nonvolatile memory (not shown) such as an EEPROM in which a control program executed by the CPU is stored, a RAM (not shown) for temporarily storing data, Peripheral circuits such as a communication interface circuit for performing communication between the main controller 20 and the LCD module 40 are provided.

  The panel control unit 30 communicates with the main control unit 20 by the CPU executing a control program stored in the nonvolatile memory, and controls the LCD module 40 under the instruction of the main control unit 20. . Details of the panel control unit 30 will be described later.

  The LCD module 40 includes an LCD (Liquid Crystal Display) 41 that displays various images. As will be described later, the LCD module 40 receives image data and a display instruction signal output by the panel control unit 30. The LCD module 40 displays an image indicated by the image data on the LCD 41 based on the input image data and the display instruction signal. Details of the LCD module 40 will be described later.

  The image formation control unit 50 includes a CPU (not shown), a nonvolatile memory (not shown) such as an EEPROM in which a control program executed by the CPU is stored, and a RAM (not shown) for temporarily storing data. A peripheral circuit such as a communication interface circuit for performing communication with the main control unit 20 is provided.

  The image formation control unit 50 communicates with the main control unit 20 by the CPU executing a control program stored in the non-volatile memory, and forms an image on a sheet under the instruction of the main control unit 20. The image forming operation to be controlled is controlled.

  The power supply unit 90 includes an AC / DC converter (not shown) and the like, and is connected to a commercial AC power supply (not shown) via a main switch (not shown). When the main switch is in the closed state, the power supply unit 90 uses the commercial AC voltage supplied from the commercial AC power source to operate each operation unit (the input operation unit 80, the energy saving control unit 10, the main control unit 20) in the copying machine 1. The power supply voltage used for the operation of the panel control unit 30, the LCD module 40, and the image formation control unit 50) is generated. The power supply unit 90 supplies the generated power supply voltage to each operation unit via a power supply line (not shown).

  The energy saving control unit 10 includes a CPU (not shown), a nonvolatile memory (not shown) such as an EEPROM in which a control program executed by the CPU is stored, a RAM (not shown) for temporarily storing data, These peripheral circuits are provided.

  The energy saving control unit 10 switches the power mode between the normal mode and the sleep mode. The normal mode is a power mode in which the power supply voltage generated by the power supply unit 90 is supplied to all the operation units in the copying machine 1 so that all the operation units are in a power supply state. On the other hand, in the sleep mode, the power supply voltage is supplied to the input operation unit 80, the energy saving control unit 10, and the LCD module 40, and the other operation units (main control unit 20, panel control unit 30, and image formation control unit 50). ) Is a power mode in which the supply of the power supply voltage is cut off and the other operation units are brought into a non-feed state.

  The energy-saving control unit 10, the main control unit 20, the panel control unit 30, and the LCD module 40 constitute the display control device 2 according to an embodiment of the display control device according to the present invention. Hereinafter, details of the display control device 2 will be described. FIG. 2 is a block diagram showing an electrical configuration of the display control apparatus 2 according to an embodiment of the display control apparatus of the present invention.

  As shown in FIG. 2, the display control device 2 includes an energy saving control unit 10, power feeding switches SW1 and SW2, a main control unit 20, a panel control unit 30, a reset signal output circuit 21 (signal switching unit), And an LCD module 40.

  The power supply voltage V <b> 1 is constantly supplied from the power supply unit 90 to the energy saving control unit 10. Further, the energy saving control unit 10 receives a mode switching signal MOD indicating that a mode switching key included in the input operation unit 80 has been pressed. On the other hand, the energy saving control unit 10 outputs open / close instruction signals ST1a and ST2a indicating instructions for opening and closing the power supply switches SW1 and SW2, and a switching instruction signal MDC indicating a power mode switching instruction. Input / output operations of various signals in the energy saving control unit 10 will be described later.

  The power supply switch SW <b> 1 is an open / close switch that switches whether the power supply voltage V <b> 2 supplied from the power supply unit 90 is supplied to the main control unit 20. The power supply switch SW1 opens and closes according to an instruction indicated by an opening / closing instruction signal ST1a output from the energy saving control unit 10 and an opening / closing instruction signal ST1b described later output from the main control unit 20.

  The power supply switch SW <b> 2 is an open / close switch that switches whether to supply the power supply voltage V <b> 3 supplied from the power supply unit 90 to the panel control unit 30. The power supply switch SW2 opens and closes according to an instruction indicated by an opening / closing instruction signal ST2a output from the energy saving control unit 10 and an opening / closing instruction signal ST2b described later output from the panel control unit 30.

  When the power supply switch SW1 is closed, the main control unit 20 is supplied with the power supply voltage V2 from the power supply unit 90 via the power supply switch SW1. Further, the switching instruction signal MDC output from the energy saving control unit 10 is input to the main control unit 20. On the other hand, the main control unit 20 outputs an opening / closing instruction signal ST1b indicating an instruction to open / close the power supply switch SW1. The main controller 20 communicates with the panel controller 30 via the communication interface circuit. Various signal input / output operations in the main control unit 20 and communication operations with the panel control unit 30 will be described later.

  The panel control unit 30 is supplied with the power supply voltage V3 from the power supply unit 90 via the power supply switch SW2 when the power supply switch SW2 is in the closed state. On the other hand, the panel control unit 30 opens / closes an instruction signal ST2b indicating an instruction to open / close the power supply switch SW2, image data IMG indicating an image to be displayed on the LCD 41, and image data stored in an image storage unit 43 described later. Among them, a display instruction signal ADR for instructing an image to be displayed on the LCD 41 is output. The panel control unit 30 communicates with the main control unit 20 via a communication interface circuit (not shown). The input / output operation of various signals in the panel control unit 30 and the communication operation with the main control unit 20 will be described later.

  Further, the panel control unit 30 outputs a reset signal RST indicating a high level when the power supply voltage V3 is supplied and the power supply state is provided. On the other hand, the panel control unit 30 outputs a reset signal RST indicating a low (0) level when the supply of the power supply voltage V3 is interrupted and is in a non-powered state.

  The reset signal output circuit 21 switches the reset signal RST output from the panel control unit 30 to the reset signal RST indicating a high level and outputs the reset signal RST to the LCD module 40. Specifically, the reset signal output circuit 21 includes resistors R1, R2, R3, and a transistor switch SW3. The reset signal RST output from the panel control unit 30 is input to the reset signal output circuit 21. The reset signal output circuit 21 is constantly supplied with the power supply voltage V5 from the power supply unit 90.

  When a reset signal RST indicating a high level is input to the reset signal output circuit 21, the reset signal RST is input to the transistor switch SW3 via the resistor R2, so that the transistor switch SW3 is closed. As a result, the current that flows when the power supply voltage V5 is supplied flows to the ground via the resistor R1. That is, when the reset signal RST indicating the high level is input, the reset signal output circuit 21 outputs the high level reset signal RST corresponding to the voltage level of the voltage generated in the resistor R1 to the reset input terminal REST of the LCD module 40. Output to.

  On the other hand, when the reset signal RST indicating the low (0) level is input to the reset signal output circuit 21, the transistor switch SW3 is in the closed state even if the reset signal RST is input to the transistor switch SW3 via the resistor R2. It becomes an open state without becoming. As a result, the current that flows due to the supply of the power supply voltage V5 flows to the reset input terminal REST of the LCD module 40. That is, when the reset signal RST indicating the low (0) level is input, the reset signal output circuit 21 outputs the high level reset signal RST corresponding to the voltage level of the power supply voltage V5 to the reset input of the LCD module 40. Output to terminal REST.

  The LCD module 40 includes a power supply terminal VDD, a data input terminal SI, an instruction signal input terminal A0, a reset input terminal REST, and a ground terminal GND. The power supply voltage V4 supplied from the power supply unit 90 is always input to the power supply terminal VDD. The image data IMG output from the panel control unit 30 is input to the data input terminal SI. The display instruction signal ADR output from the panel control unit 30 is input to the instruction signal input terminal A0. The reset signal RST output from the reset signal output circuit 21 is input to the reset input terminal REST. The ground terminal GND is connected to the ground.

  The LCD module 40 includes an LCD 41, a segment driver and a common driver (not shown), and an LCD driver 42. The LCD 41, the segment driver, the common driver, and the LCD driver 42 operate using the power supply voltage V4 supplied via the power supply terminal VDD.

  The LCD 41 is, for example, a so-called simple matrix type (STN (Super Twisted Nematic) type liquid crystal display) in which a liquid crystal cell is sandwiched at each intersection of a plurality of segment power supply lines and a plurality of common power supply lines orthogonal thereto. A segment voltage supplied via a segment power supply line and a common voltage supplied via a common power supply line are applied to both ends of each liquid crystal cell. Depending on the level, the orientation of the liquid crystal molecules is changed to adjust the light transmission, thereby displaying an image with each liquid crystal cell as each pixel.

  The segment driver generates each segment voltage at a level designated by the LCD driver 42 and supplies the generated segment voltage to each segment power supply line provided in the LCD 41. The common driver generates each common voltage at a level designated by the LCD driver 42 and supplies the generated common voltage to each common power supply line provided in the LCD 41.

  The LCD driver 42 includes a CPU (not shown), a nonvolatile memory (not shown) such as an EEPROM storing a control program executed by the CPU, an image storage unit 43, a data input terminal SI, and an instruction signal input terminal A0. , And an interface circuit (not shown) that receives various signals input to the reset input terminal REST and peripheral circuits thereof.

  The image storage unit 43 is configured by a volatile memory such as a RAM. The image storage unit 43 is provided with two storage areas capable of storing one image data IMG. Hereinafter, of the two storage areas, a storage area closer to the head address of the volatile memory constituting the image storage unit 43 is referred to as a first storage area. Of the two storage areas, a storage area far from the head address of the volatile memory constituting the image storage unit 43 is referred to as a second storage area.

  The LCD driver 42 operates as described below when the CPU executes a control program stored in the nonvolatile memory. The LCD driver 42 receives the image data IMG and the display instruction signal ADR output from the panel control unit 30 using an interface circuit (not shown). The LCD driver 42 stores the received image data IMG in one of the first storage area and the second storage area provided in the image storage unit 43. The display instruction signal ADR indicates the head address of one of the first storage area and the second storage area provided in the image storage unit 43.

  Further, the LCD driver 42 reads the image data IMG stored in the storage area corresponding to the head address indicated by the received display instruction signal ADR from the image storage unit 43. Then, the LCD driver 42 determines the level of the segment voltage and the common voltage to be applied to each liquid crystal cell corresponding to each pixel based on the pixel value (gradation value) of each pixel of the image indicated by the read image data IMG. To decide. Then, the LCD driver 42 supplies the determined segment voltage and common voltage to the segment power supply line and the common power supply line that sandwich each liquid crystal cell by the segment driver and the common driver.

  As a result, the segment voltage and the common voltage supplied via the segment feed line and the common feed line are applied to both ends of each liquid crystal cell. Thereby, each liquid crystal cell changes the direction of the liquid crystal molecules according to the level of the applied segment voltage and common voltage, and adjusts the light transmittance. As a result, an image composed of each pixel corresponding to each liquid crystal cell is displayed on the LCD 41.

  The LCD driver 42 causes the segment driver and the common driver to supply the segment voltage and the common voltage when the reset signal RST input to the reset input terminal REST indicates a high level. On the other hand, when the reset signal RST input to the reset input terminal REST indicates a low level, the LCD driver 42 stops the supply of the segment voltage and the common voltage by the segment driver and the common driver.

  Therefore, when the reset signal RST input to the reset input terminal REST indicates a high level, an image is displayed on the LCD 41. On the other hand, when the input reset signal RST indicates a low level, an image is displayed on the LCD 41. Disappears. That is, the LCD driver 42 displays an image on the LCD 41 when the reset signal RST input to the reset input terminal REST indicates a high level. On the other hand, the LCD driver 42 does not display an image on the LCD 41 when the reset signal RST input to the reset input terminal REST indicates a low level.

  Hereinafter, the operation of the display control device 2 according to the power mode will be described. FIG. 3 is a sequence diagram showing an example of the operation of the display control device 2 at the beginning of power-on.

  When the main switch (not shown) of the power supply unit 90 is closed and the power supply voltage V1 is supplied from the power supply unit 90 to the energy saving control unit 10, the energy saving control unit 10 switches the power mode to the normal mode. Specifically, as shown in FIG. 3, the energy saving control unit 10 outputs opening / closing instruction signals ST1a and ST2a indicating an instruction to close the power feeding switches SW1 and SW2. As a result, the power supply switches SW1 and SW2 are closed according to the instructions indicated by the opening / closing instruction signals ST1a and ST2a. As a result, the power supply voltage V2 is supplied to the main control unit 20, and the main control unit 20 enters a power supply state. Further, the power supply voltage V3 is supplied to the panel control unit 30, and the panel control unit 30 enters a power supply state (S1).

  When the main control unit 20 enters the power supply state, the main control unit 20 starts an initialization process. In the initialization process, the main control unit 20 first initializes the communication interface circuit so that communication with the panel control unit 30 is possible. On the other hand, the panel control unit 30 also starts the initialization process when it enters the power supply state. In the initialization process, the panel control unit 30 initializes the communication interface circuit and enters a state in which communication with the main control unit 20 is possible.

  And the energy-saving control part 10 outputs the switching instruction | indication signal MDC (henceforth a starting instruction | indication signal) which shows switching a power mode to normal mode at the time of starting after power activation to the main control part 20 (S2).

  When the activation instruction signal is input, the main control unit 20 transmits activation instruction information indicating that the power mode is switched to the normal mode at the time of activation after power-on to the panel control unit 30 (S3).

  When the panel control unit 30 receives the activation instruction information, the panel control unit 30 determines that the power mode is switched to the normal mode at the time of activation after power-on. When the panel control unit 30 makes the determination, the panel control unit 30 outputs image data IMG indicating the startup display image stored in advance in the nonvolatile memory of the panel control unit 30 to the LCD module 40 (S4). The startup display image is an image that is predetermined as an image indicating that the copying machine 1 is starting up. For example, the startup display image includes an image showing a logo of the manufacturer of the copying machine 1.

  In the LCD module 40, when the image data IMG indicating the startup display image is input to the data input terminal SI, the LCD driver 42 receives the input image data IMG in the first storage area provided in the image storage unit 43. (S5).

  In step S4, the panel control unit 30 outputs the display instruction signal ADR indicating the head address of the first storage area to the LCD module 40 after outputting the image data IMG indicating the startup display image (S6).

  On the other hand, in the LCD module 40, when the display instruction signal ADR indicating the start address of the first storage area is input to the instruction signal input terminal A0, the LCD driver 42 displays an image indicating a startup display image from the first storage area. Read data IMG. Then, the LCD driver 42 supplies the segment driver and the common driver with the segment voltage and the common voltage at a level determined based on the pixel value of each pixel of the startup display image indicated by the read image data IMG. As a result, the LCD driver 42 displays a startup display image on the LCD 41 (S7).

  On the other hand, after transmitting the activation instruction information to the panel control unit 30 in step S3, the main control unit 20 reads various data used for control of the panel control unit 30 and the image formation control unit 50 from the nonvolatile memory and stores them in the RAM. The initialization process such as performing is continued (S8).

  When the initialization process is completed, the main control unit 20 transmits image data IMG indicating the initial display image stored in the RAM in the initialization process to the panel control unit 30 (S9). The initial display image is an image showing an operation screen for the user to first operate the copying machine 1 when the main control unit 20 completes the initialization process and the copying machine 1 becomes operable. . For example, the initial display image is an image showing an operation screen on which soft keys pressed to display each operation screen for inputting each condition (for example, the number of copies, density, and aggregation setting) of the image forming operation are arranged. Etc.

  On the other hand, when the panel control unit 30 receives the image data IMG indicating the initial display image after executing step S6, the panel control unit 30 determines that the initialization process in the main control unit 20 has been completed. When the panel control unit 30 makes the determination, the panel control unit 30 outputs image data IMG indicating the received initial display image to the LCD module 40 (S10). In the LCD module 40, when the image data IMG indicating the initial display image is input to the data input terminal SI, the LCD driver 42 stores the input image data IMG in the first storage area (S11).

  Further, after outputting the image data IMG indicating the initial display image in step S10, the panel control unit 30 outputs the display instruction signal ADR indicating the head address of the first storage area to the LCD module 40 (step S6). S12). On the other hand, in the LCD module 40, when the display instruction signal ADR indicating the head address of the first storage area is input to the instruction signal input terminal A0, the LCD driver 42 starts from the first storage area in the same manner as in step S7. The image data IMG indicating the display image is read out, and the initial display image is displayed on the LCD 41 (S13).

  Thereafter, when a user who visually recognizes the operation screen indicated by the initial display image performs various input operations via the input operation unit 80, the main control unit 20 receives the input operation. When the input operation indicates an instruction to display an image on the LCD 41, the main control unit 20 transmits image data IMG indicating an image to be displayed to the panel control unit 30 as in step S9. Thereafter, the same processing as in steps S10 to S13 is performed, and as a result, the display target image is displayed on the LCD 41. In this way, the panel control unit 30 controls the LCD module 40 under the instruction from the main control unit 20 and causes the LCD 41 to display the instructed image.

  Next, the operation of the display control device 2 when the power mode is switched from the normal mode to the sleep mode will be described. FIG. 4 is a sequence diagram illustrating an example of the operation of the display control device 2 when the power mode is switched from the normal mode to the sleep mode.

  When the power mode is the normal mode, the energy saving control unit 10, for example, when no operation is performed through the input operation unit 80 for a certain period of time or when the mode switching key included in the input operation unit 80 is pressed. Thus, when the mode switching signal MOD is input, the power mode is switched from the normal mode to the sleep mode. Specifically, as shown in FIG. 4, the energy saving control unit 10 outputs a switching instruction signal MDC (hereinafter referred to as a sleep instruction signal) indicating that the power mode is switched from the normal mode to the sleep mode to the main control unit 20. (S21).

  When the sleep instruction signal is input, the main control unit 20 transmits sleep instruction information indicating that the power mode is switched to the sleep mode to the panel control unit 30 (S22). Further, the main control unit 20 transmits image data IMG indicating the sleep display image and the display image during return stored in the RAM in the initialization process to the panel control unit 30 (S23).

  The sleep display image is an image that is predetermined as an image indicating that the power mode is the sleep mode, and includes, for example, an image indicating a message (character string) indicating that the power mode is the sleep mode. . The display image during return is an image that is predetermined as an image indicating that the power mode is returning from the sleep mode to the normal mode. For example, a message indicating that the power mode is returning from the sleep mode to the normal mode. It is composed of an image or the like indicating (character string).

  When receiving the sleep instruction information transmitted in step S22, panel control unit 30 determines that the power mode is switched from the normal mode to the sleep mode. When the panel control unit 30 receives the image data IMG indicating the sleep display image and the returning display image after the determination, the panel control unit 30 outputs the received two image data IMG to the LCD module 40 (S24).

  On the other hand, in the LCD module 40, when two image data IMG indicating the sleep display image and the returning display image are input to the data input terminal SI, the LCD driver 42 displays the image data indicating the input sleep display image. The IMG is stored in a first storage area provided in the image storage unit 43. Further, the LCD driver 42 stores the input image data IMG indicating the displayed display image during return in a second storage area provided in the image storage unit 43 (S25).

  Then, after executing step S24, the panel control unit 30 outputs a display instruction signal ADR indicating the head address of the first storage area to the LCD module 40 (S26). On the other hand, in the LCD module 40, when the display instruction signal ADR indicating the head address of the first storage area is input to the instruction signal input terminal A0, the LCD driver 42 sleeps from the first storage area in the same manner as in step S7. The image data IMG indicating the display image is read, and the sleep display image is displayed on the LCD 41 (S27).

  Further, after executing step S23, the main control unit 20 outputs an opening / closing instruction signal ST1b indicating an instruction to open the power supply switch SW1. As a result, the power supply switch SW1 is opened according to the instruction indicated by the opening / closing instruction signal ST1b. As a result, the supply of the power supply voltage V2 to the main control unit 20 is interrupted, and the main control unit 20 enters a non-power supply state (S28).

  Moreover, the panel control part 30 outputs the opening / closing instruction | indication signal ST2b which shows the instruction | indication which makes power supply switch SW2 into an open state after performing step S26. As a result, the power supply switch SW2 is opened according to the instruction indicated by the opening / closing instruction signal ST2b. As a result, the supply of the power supply voltage V3 to the panel control unit 30 is cut off, and the panel control unit 30 enters a non-power supply state (S29).

  Even when the panel control unit 30 is in a non-powered state in step S29, as described above, the reset signal output circuit 21 outputs the high-level reset signal RST to the panel control unit 30 to the LCD module 40. . For this reason, after the LCD driver 42 displays the sleep display image on the LCD 41 in step S27, the LCD driver 42 continues to display the sleep display image on the LCD 41 even if the panel control unit 30 enters a non-powered state.

  Next, the operation of the display control device 2 when the power mode is switched from the sleep mode to the normal mode will be described. FIG. 5 is a sequence diagram illustrating an example of the operation of the display control device 2 when the power mode is switched from the sleep mode to the normal mode.

  When the power mode is the sleep mode and the mode switching signal MOD is input when the mode switching key included in the input operation unit 80 is pressed when the power mode is the sleep mode, the energy saving control unit 10 changes the power mode from the sleep mode to the normal mode. Switch to mode. Specifically, as shown in FIG. 5, the energy saving control unit 10 outputs open / close instruction signals ST1a and ST2a indicating an instruction to close the power feeding switches SW1 and SW2. As a result, the power supply switches SW1 and SW2 are closed according to the instructions indicated by the opening / closing instruction signals ST1a and ST2a. As a result, the power supply voltage V2 is supplied to the main control unit 20, and the main control unit 20 enters a power supply state. Further, the power supply voltage V3 is supplied to the panel control unit 30, and the panel control unit 30 enters a power supply state (S31).

  When the main control unit 20 enters the power supply state, the main control unit 20 starts an initialization process. In the initialization process, the main control unit 20 first initializes the communication interface circuit so that communication with the panel control unit 30 is possible. On the other hand, the panel control unit 30 also starts the initialization process when it enters the power supply state. In the initialization process, the panel control unit 30 initializes the communication interface circuit and enters a state in which communication with the main control unit 20 is possible.

  Then, the energy saving control unit 10 outputs a switching instruction signal MDC (hereinafter referred to as a return instruction signal) indicating that the power mode is switched from the sleep mode to the normal mode to the main control unit 20 (S32).

  When the return instruction signal is input, the main control unit 20 transmits return instruction information indicating that the power mode is switched from the sleep mode to the normal mode to the panel control unit 30 (S33).

  When receiving the return instruction information, panel control unit 30 determines that the power mode is returning from the sleep mode to the normal mode. When the panel control unit 30 makes the determination, the panel control unit 30 outputs a display instruction signal ADR indicating the head address of the second storage area to the LCD module 40 (S34).

  In the LCD module 40, after executing step S27 (FIG. 4), the LCD driver 42 continues to display the sleep display image on the LCD 41 while the power mode is the sleep mode. In the LCD module 40, when the display instruction signal ADR indicating the head address of the second storage area is input to the instruction signal input terminal A0 by executing step S34, the LCD driver 42 is returning from the second storage area. Image data IMG indicating the display image is read out, and the display image during return is displayed on the LCD 41 in the same manner as in step S7 (S35).

  On the other hand, even after the return instruction information is transmitted to the panel control unit 30 in step S33, the main control unit 20 reads various data used for control of the panel control unit 30 and the image formation control unit 50 from the nonvolatile memory and stores them in the RAM. The initialization process such as performing is continued (S36).

  When the initialization process is completed, the main control unit 20 transmits image data IMG indicating the display image after restoration read and stored in the RAM in the initialization process to the panel control unit 30 (S37). When the power mode is switched from the sleep mode to the normal mode, the display image after returning is first displayed to the user when the main control unit 20 completes the initialization process and the copying machine 1 becomes operable. 3 is an image showing an operation screen for operating the copying machine 1. For example, the post-return display image is composed of an image showing the same operation screen as the initial display image.

  The post-return display image is not limited to being composed of an image showing the same operation screen as the initial display image. For example, when the power mode is switched from the normal mode to the sleep mode, the main control unit 20 performs the opening / closing instruction before outputting the opening / closing instruction signal ST1b indicating an instruction to open the power supply switch SW1 in step S28. The image data IMG indicating the image displayed before outputting the signal ST1b may be stored in the nonvolatile memory as the image data IMG indicating the display image after return.

  When the panel control unit 30 receives the image data IMG indicating the display image after return after the execution of step S34, the initialization process in the main control unit 20 is completed, and it is determined that the return from the sleep mode to the normal mode is completed. To do. When the panel control unit 30 makes the determination, the panel control unit 30 outputs the received image data IMG indicating the display image after return to the LCD module 40 (S38). In the LCD module 40, when the image data IMG indicating the display image after return is input to the data input terminal SI, the LCD driver 42 receives the input image data IMG in the first storage area provided in the image storage unit 43. (S39).

  Further, after outputting the image data IMG indicating the display image after the return in step S38, the panel control unit 30 outputs the display instruction signal ADR indicating the head address of the first storage area to the LCD module 40 in the same manner as in step S6. (S40). On the other hand, in the LCD module 40, when the display instruction signal ADR indicating the head address of the first storage area is input to the instruction signal input terminal A0, the LCD driver 42 returns from the first storage area in the same manner as in step S7. Image data IMG indicating the post-display image is read, and the post-return display image is displayed on the LCD 41 (S41).

  According to the configuration of the above embodiment, when the power mode is switched to the sleep mode by the energy saving control unit 10, the main control unit 20 and the panel control unit 30 are in a non-powered state. For this reason, when the power mode is the sleep mode, the main control unit 20 and the panel control unit 30 are set when the power mode is the sleep mode, as compared with the configuration in which the main control unit 20 and the panel control unit 30 are in the power supply state. It is possible to suppress the power consumption consumed by.

  In addition, according to the configuration of the above embodiment, when the power mode is switched to the sleep mode, the sleep display image and the returning display image transmitted by the main control unit 20 are stored in the image storage unit 43, and the sleep display is displayed on the LCD 41. An image is displayed. The LCD module 40 is in the power supply state even when the power mode is the sleep mode.

  Therefore, the LCD module 40 can continue to display the sleep display image on the LCD 41 while the power mode is the sleep mode. As a result, the user can accurately grasp that the current power mode is the sleep mode by viewing the sleep display image while the power mode is the sleep mode.

  Since the LCD module 40 is in the power supply state while the power mode is the sleep mode, the state where the display image during return is stored in the image storage unit 43 is maintained. In addition, when the power mode is switched from the sleep mode to the normal mode, the panel control unit 30 allows the main control unit 20 to complete the predetermined initialization process performed at the beginning of the power supply state. The returning display image stored in the image storage unit 43 is displayed on the LCD 41. For this reason, the user does not finish the predetermined initialization process that is initially performed when the main control unit 20 enters the power supply state by visually recognizing the display image during return, and the power mode is returning from the sleep mode to the normal mode. It is possible to accurately grasp that.

  Further, according to the configuration of the above embodiment, even when the panel control unit 30 is in a non-power supply state when the power mode is switched to the sleep mode, the reset signal output circuit 21 is at the high level. A reset signal RST is output to the LCD module 40. Therefore, the LCD module 40 can continue displaying the sleep display image without hiding the sleep display image displayed when the power mode is switched to the sleep mode while the power mode is the sleep mode. it can.

  In the above embodiment, the configurations shown in FIGS. 1 and 5 are merely examples, and the present invention is not limited to the embodiment.

  For example, the startup display image may be stored in the nonvolatile memory of the main control unit 20, and the startup display image may not be stored in the nonvolatile memory of the panel control unit 30. In accordance with this, the main control unit 20 transmits the start instruction information to the panel control unit 30 in step S3 (FIG. 3), and then shows the start-up display image stored in the nonvolatile memory of the main control unit 20. The data IMG may be read and the image data IMG may be transmitted to the panel control unit 30. Accordingly, instead of step S4, the panel control unit 30 receives the image data IMG indicating the startup display image transmitted by the main control unit 20, and receives the received image data IMG indicating the startup display image. It may be transmitted to the LCD module 40.

1 Copying machine (electronic equipment)
2 Display control device 10 Energy saving control unit 20 Main control unit 21 Reset signal output circuit (signal switching unit)
30 Panel control unit 40 LCD module (display device)
41 LCD (display unit)
42 LCD driver 43 Image storage unit 80 Input operation unit RST Reset signal

Claims (4)

A display device comprising: a display unit for displaying an image; and an image storage unit for storing the image;
A panel control unit for controlling the display device;
A main control unit for controlling the panel control unit;
A normal mode in which the display device, the panel control unit, and the main control unit are in a power supply state, and a sleep mode in which the display device is in a power supply state and the panel control unit and the main control unit are in a non-power supply state An energy-saving control unit that switches the power mode between
With
The main control unit is configured to display a sleep display image indicating that the power mode is the sleep mode and the power mode from the sleep mode to the normal mode when the energy saving control unit switches the power mode to the sleep mode. After returning to the panel control unit and indicating that the display image during return indicating that it is returning to the non-power supply state,
The panel control unit is configured to use the sleep display image as an image to be displayed on the display unit among the transmitted sleep display image and the return display image and an image stored in the image storage unit. after a first signal instructing the outputs to the display device, Ri Do the unpowered state,
When the sleep display image, the returning display image, and the first signal are input, the display device stores the input sleep display image and the returning display image in the image storage unit. A display control device that reads the sleep display image indicated by the input first signal from the image storage unit and displays the sleep display image on the display unit. When the energy saving control unit switches the power mode from the sleep mode to the normal mode, the panel control unit is an image to be displayed on the display unit among images stored in the image storage unit. , Outputting a second signal indicating the display image during return to the display device,
When the second signal is input, the display device reads the returning display image indicated by the input second signal from the image storage unit, and displays the returning display image on the display unit. The display control apparatus according to claim 1, wherein the display is displayed. The display device receives a reset signal indicating a high level or a low level. When the input reset signal indicates a high level, the display unit displays an image, while the input reset signal is a low level. When indicating the level, do not display an image on the display unit,
The panel control unit outputs the reset signal indicating a low level when in a non-powered state,
The display control device includes:
The display control device according to claim 1, further comprising: a signal switching unit that switches the reset signal output from the panel control unit to the reset signal indicating a high level and outputs the signal to the display device. An electronic device comprising the display control device according to any one of claims 1 to 3,
An electronic device comprising an input operation unit for allowing a user to input an operation instruction for the electronic device.

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